Wrong occurance on day of daylight savings change

[anupvarghese]

Yes, it looks a bit confusing from the issue header. Here is the description

Today (2nd - Oct -2016 -Australia/Sydney) time has changed with a daylight savings (1 hr further).

I have the below snippet to explain the issue,
By the iCal string it is scheduled to run Weekly by Sunday at 16 HRS

const rrule = require('rrule');
const moment = require('moment-timezone');
let opts = rrule.RRule.parseString('FREQ=WEEKLY;BYDAY=SU;BYHOUR=16;BYMINUTE=00')
opts.dtstart = moment.tz('Australia/Sydney').subtract('30', 'days').toDate();
const rule = new rrule.RRule(opts)
const today = moment.tz('Australia/Sydney').startOf('day')();
rule.after(today, true);

Here is what I get when I run the below,

> rule.between(new Date(2016, 8, 1), new Date(2016, 10, 1)).map(p => console.log(p));

Sun Sep 04 2016 16:00:56 GMT+1000 (AEST)
Sun Sep 11 2016 16:00:56 GMT+1000 (AEST)
Sun Sep 18 2016 16:00:56 GMT+1000 (AEST)
Sun Sep 25 2016 16:00:56 GMT+1000 (AEST)
Sat Oct 01 2016 16:00:56 GMT+1000 (AEST)
Sun Oct 09 2016 16:00:56 GMT+1100 (AEDT)
Sun Oct 16 2016 16:00:56 GMT+1100 (AEDT)
Sun Oct 23 2016 16:00:56 GMT+1100 (AEDT)
Sun Oct 30 2016 16:00:56 GMT+1100 (AEDT)

On the day when the day light savings changed, it is behaving differently (Look at the bold text)

[deep-c]

Same issue here. using rrulestr to parse the following RRULE:FREQ=DAILY;UNTIL=20161005T000000Z\nEXRULE:FREQ=DAILY;UNTIL=20160925T000000Z, I get the following list of dates:

Mon Sep 26 2016 00:00:00 GMT+1000 (AEST)
Tue Sep 27 2016 00:00:00 GMT+1000 (AEST)
Wed Sep 28 2016 00:00:00 GMT+1000 (AEST)
Thu Sep 29 2016 00:00:00 GMT+1000 (AEST)
Fri Sep 30 2016 00:00:00 GMT+1000 (AEST)
Sat Oct 01 2016 00:00:00 GMT+1000 (AEST)
Mon Oct 03 2016 00:00:00 GMT+1100 (AEDT)
Tue Oct 04 2016 00:00:00 GMT+1100 (AEDT)
Wed Oct 05 2016 00:00:00 GMT+1100 (AEDT)

OCT 2 is missing.

[raphaelm]

For our use cases, it can apparently be fixed by just removing timezone awareness from fromOrdinal, which appears to make sense since toOrdinal apparently removes timezone information already.

    fromOrdinal: function (ordinal) {
      var millisecsFromBase = ordinal * dateutil.ONE_DAY
      return new Date(dateutil.ORDINAL_BASE.getTime() +
        millisecsFromBase);
    },

I'm not sure if this has implications that I'm not aware of, though, since I did not dive deep into the code. @espen @jakubroztocil do you see any problems with this or should I create a PR?

[SystemParadox]

I have a similar issue (UK timezone):

var { RRule } = require('rrule');
var rule = new RRule({
    freq: RRule.WEEKLY,
    dtstart: new Date(2018, 9, 22, 12),
    until: new Date(2018, 10, 19, 12),
});
console.log(rule.all());

In rrule 2.2.9 this gives:

[ 2018-10-22T11:00:00.000Z,
  2018-10-28T12:00:00.000Z,
  2018-11-05T12:00:00.000Z,
  2018-11-12T12:00:00.000Z,
  2018-11-19T12:00:00.000Z ]

Daylight savings time ends on the 28th October. All the occurrences from this date onwards are shifted one day earlier.

The above change to fromOrdinal appears to fix it.

[davidgoli]

@anupvarghese I believe this has been fixed in 2.3.4.